Effect of Additional Structure on Effective Stack Height of Gas Dispersion in Atmosphere

Wind-tunnel experiments were conducted to evaluate the effect of additional structure (building, sea wall and banking) on the effective stack height, which is usually used in safety analyses of nuclear power facilities in Japan. The effective stack heights were estimated with and without the additional structure in addition to the reactor building while varying several conditions such as the source height, the height of additional structure and the distance between the source position and the additional structure. When the source height is equivalent to the reactor building height, the additional structure enhances both the vertical and horizontal gas dispersion widths and decreases the ground gas concentration, and it means that the additional structure does not decrease the effective stack height. When the source height is larger than the reactor height, the additional structures might affect the effective stack height. As the distance between the source and the additional structure decreases, or as the height of the additional structure increases, the structure has a larger effect on the effective stack height

Rationale, Design, and Baseline Characteristics of the CURRENT AS Registry-2

BACKGROUND: There is scarce data evaluating the current practice pattern and clinical outcomes for patients with severe aortic stenosis (AS), including both those who underwent surgical aortic valve replacement (SAVR) or transcatheter aortic valve implantation (TAVI) and those who were managed conservatively in the TAVI era.Methods and Results: The Contemporary outcomes after sURgery and medical tREatmeNT in patients with severe Aortic Stenosis (CURRENT AS) Registry-2 is a prospective, physician-initiated, multicenter registry enrolling consecutive patients who were diagnosed with severe AS between April 2018 and December 2020 among 21 centers in Japan. The rationale for the prospective enrollment was to standardize the assessment of symptomatic status, echocardiographic evaluation, and other recommended diagnostic examinations such as computed tomography and measurement of B-type natriuretic peptide. Moreover, the schedule of clinical and echocardiographic follow up was prospectively defined and strongly recommended for patients who were managed conservatively. The entire study population consisted of 3, 394 patients (mean age: 81.6 years and women: 60%). Etiology of AS was degenerative in 90% of patients. AS-related symptoms were present in 60% of patients; these were most often heart failure symptoms. The prevalence of high- and low-gradient AS was 58% and 42%, respectively, with classical and paradoxical low-flow low-gradient AS in 4.5% and 6.7%, respectively. CONCLUSIONS: The CURRENT AS Registry-2 might be large and meticulous enough to determine the appropriate timing of intervention for patients with severe AS in contemporary clinical practice

Should Lymph Nodes Be Retrieved in Patients with Intrahepatic Cholangiocarcinoma? A Collaborative Korea-Japan Study

Simple Summary Intrahepatic cholangiocarcinoma (IHCC) is the second most common primary hepatic malignant tumor after hepatocellular carcinoma (HCC). The prevalence of lymph node metastases (LNM) detected at surgery for IHCC has been reported as 25-50%, and lymph node metastasis is known to be significantly associated with poor survival outcomes. However, the oncologic value of lymph node dissection in resected IHCC is still controversial. According to the present Korea-Japan international collaborative study, it was found that surgical retrieval of more than four lymph nodes (>= 4 LNs) could improve survival outcome in resected IHCC with LNM. Based on preoperatively detectable parameters, a nomogram was established to predict LNM to suggest tailored intraoperative LN management in patients with IHCC. Further prospective research is needed to validate the present surgical strategy in resected IHCC. Background: This study was performed to investigate the oncologic role of lymph node (LN) management and to propose a surgical strategy for treating intrahepatic cholangiocarcinoma (IHCC). Methods: The medical records of patients with resected IHCC were retrospectively reviewed from multiple institutions in Korea and Japan. Short-term and long-term oncologic outcomes were analyzed according to lymph node metastasis (LNM). A nomogram to predict LNM in treating IHCC was established to propose a surgical strategy for managing IHCC. Results: A total of 1138 patients were enrolled. Of these, 413 patients underwent LN management and 725 did not. A total of 293 patients were found to have LNM. The No. 12 lymph node (36%) was the most frequent metastatic node, and the No. 8 lymph node (21%) was the second most common. LNM showed adverse long-term oncologic impact in patients with resected IHCC (14 months, 95% CI (11.4-16.6) vs. 74 months, 95% CI (57.2-90.8), p < 0.001), and the number of LNM (0, 1-3, 4 <=) was also significantly related to negative oncologic impacts in patients with resected IHCC (74 months, 95% CI (57.2-90.8) vs. 19 months, 95% CI (14.4-23.6) vs. 11 months, 95% CI (8.1-13.8)), p < 0.001). Surgical retrieval of more than four (>= 4) LNs could improve the survival outcome in resected IHCC with LNM (13 months, 95% CI (10.4-15.6)) vs. 30 months, 95% CI (13.1-46.9), p = 0.045). Based on preoperatively detectable parameters, a nomogram was established to predict LNM according to the tumor location. The AUC was 0.748 (95% CI: 0.706-0.788), and the Hosmer and Lemeshow goodness of fit test showed p = 0.4904. Conclusion: Case-specific surgical retrieval of more than four LNs is required in patients highly suspected to have LNM, based on a preoperative detectable parameter-based nomogram. Further prospective research is needed to validate the present surgical strategy in resected IHCC.Y

Should Lymph Nodes Be Retrieved in Patients with Intrahepatic Cholangiocarcinoma? A Collaborative Korea–Japan Study

Background: This study was performed to investigate the oncologic role of lymph node (LN) management and to propose a surgical strategy for treating intrahepatic cholangiocarcinoma (IHCC). Methods: The medical records of patients with resected IHCC were retrospectively reviewed from multiple institutions in Korea and Japan. Short-term and long-term oncologic outcomes were analyzed according to lymph node metastasis (LNM). A nomogram to predict LNM in treating IHCC was established to propose a surgical strategy for managing IHCC. Results: A total of 1138 patients were enrolled. Of these, 413 patients underwent LN management and 725 did not. A total of 293 patients were found to have LNM. The No. 12 lymph node (36%) was the most frequent metastatic node, and the No. 8 lymph node (21%) was the second most common. LNM showed adverse long-term oncologic impact in patients with resected IHCC (14 months, 95% CI (11.4–16.6) vs. 74 months, 95% CI (57.2–90.8), p < 0.001), and the number of LNM (0, 1–3, 4≤) was also significantly related to negative oncologic impacts in patients with resected IHCC (74 months, 95% CI (57.2–90.8) vs. 19 months, 95% CI (14.4–23.6) vs. 11 months, 95% CI (8.1–13.8)), p < 0.001). Surgical retrieval of more than four (≥4) LNs could improve the survival outcome in resected IHCC with LNM (13 months, 95% CI (10.4–15.6)) vs. 30 months, 95% CI (13.1–46.9), p = 0.045). Based on preoperatively detectable parameters, a nomogram was established to predict LNM according to the tumor location. The AUC was 0.748 (95% CI: 0.706–0.788), and the Hosmer and Lemeshow goodness of fit test showed p = 0.4904. Conclusion: Case-specific surgical retrieval of more than four LNs is required in patients highly suspected to have LNM, based on a preoperative detectable parameter-based nomogram. Further prospective research is needed to validate the present surgical strategy in resected IHCC